The present invention concerns a device for maintaining seating zones of a flexible circuit in an electrical connector. The invention also covers the electrical connector thus equipped with this maintaining device.
The flexible circuits in question, more generally designated as xe2x80x9cflexxe2x80x9d in the field of connectors, are sheets formed from a first layer of insulating material on which are built up wiring lines of conductive material which constitute both conductors and contacts.
These wiring lines are protected and insulated by a second layer of insulating material or by a dielectric varnish.
Such flexible circuits are used in the case of multiple contacts to be disposed in a small clearance and to be rejoined at their outlet as they were at their inlet.
The width and thickness of the wiring lines determines the conductive capacity, which in turn leads to disposing, on a same flexible circuit and in a same connector, varying dimensions of contacts.
The numerous advantages of these flexible circuits have led to designers using them more and more, especially in the automotive field.
In practice, the connection of the set of contacts is effected in a single operation, generally by seating after introduction of the flexible circuit into the connector. Generally, locking means assure in a complementary manner the mechanical retention of the sheet in the said connector.
Connection devices for flexible circuits are known, in particular from French patent application No. 99/13772 now published under FR 2 800 520 A1 in the name of the same applicant, which illustrates this type of connector and this mode of connection.
To that end, the connector described in this prior art comprises a casing provided with a series of cavities for receiving contacts with terminals to be seated on the flexible circuit, and a cover element constituted of a frame provided with an opening permitting the passage of a seating tool.
Thus, the casing is present with its cover opened to permit the introduction of the contacts, then this element is closed, leaving a passage slit for inserting the flexible circuit, which immediately arrives above the contacts to be seated. The seating is done by crimping the contacts by means of a crimping tool and permits seating various contacts on the circuit.
This cover element is also provided with foldable tabs, integral with the supporting frame of the pins. Simultaneously with crimping, these tabs are folded and the pins penetrate into holes previously provided in the flexible circuit.
The pins, after passing through these holes of the flexible circuit, are retained in corresponding housings of the casing.
Although this arrangement is satisfactory from the viewpoint of contact quality, as well as mechanical resistance to detachment and reliability, there remains a difficulty in that the manufacturing is delicate in the sense that the circuits must be pre-formed with holes.
Moreover, the mechanical retention is effected only at two or three points corresponding to the holes, and could be improved.
Finally, the formation of holes requires positioning them in the circuit between the wiring lines, to the detriment of compactness.
The present invention seeks to further improve this arrangement, so as to provide a connector wherein the device for maintaining crimping zones is complete, with distributed and linear forces. Moreover, the present device, a detailed description of which will follow, is especially advantageous in the sense that it avoids any manipulation of the flexible circuit for forming holes therein, as it is, on the contrary, mounted xe2x80x9cas is.xe2x80x9d
The manufacture of the connector itself is facilitated and the mounting of the flexible circuits is also greatly simplified.
According to the present invention, the device for maintaining crimping seating zones of a flexible circuit in an electrical connector comprises a body provided on the one hand with housings adapted to receive contacts with pins to be crimped, and, on the other hand, with a flap that is moveable in rotation with respect to this body about an axis, characterized in that it comprises means for clamping the flexible circuit in the body comprising an opposed tongue and groove pair, disposed parallel to the axis of rotation of the flap.
According to a preferred embodiment, the tongue has a trapezoidal section, so as to constitute with the groove an open U-shaped offset portion.
The retaining solution consists of disposing the tongue on the flap and providing the groove in the body.
The invention also covers the electrical connector equipped with this device for maintaining crimping zones of a flexible circuit and it moreover comprises locking means for the flap when the tongue cooperates with the groove, after the flexible circuit has been positioned.
According to another characteristic, the flap is formed by molding with the body and may assume three principal positions:
an as-molded open position, with an angle of about 75xc2x0,
a delivery position permitting the insertion of the contacts and the insertion of the flexible circuit, with an angle comprised between 20xc2x0 and 5xc2x0 , and
a closure position, with no angle, upon crimping of the flexible circuit.